How to check CentOS version

There are several ways on how to check what version of CentOS is running on your system. The simplest way to check for the CentOS version number is to execute the cat /etc/centos-release command. Identifying the accurate CentOS version may be required to help you or your support team to troubleshoot your CentOS system.

Generic commands

rpm -q centos-release

$ rpm -q centos-release

CentOS version valid for CentOS 6 and higher. Causes to reveal major, minor and asynchronous CentOS version.

lsb_release -d

$ lsb_release -d

Requires redhat-lsb package to be installed before execution.

rpm -E %{rhel}

$ rpm -E %{rhel}

RPM macro to reveal a major CentOS version

rpm --eval %{centos_ver}

$ rpm --eval %{centos_ver}

RPM macro to display a major version of CentOS

cat /etc/centos-release

$ cat /etc/centos-release

Linux cat command to output content of the /etc/centos-release to query CentOS version. Works with CentOS 6 and higher.

Alternative commands to check CentOS version

In case the above-provided commands did not help you to obtain the CentOS version number you may try the following alternative commands.

Although available only for CentOS version 7 and above the hostnamectl command might provide you with a significant clue about your OS version number:

$ hostnamectl 
   Static hostname: localhost.localdomain
         Icon name: computer-vm
           Chassis: vm
        Machine ID: fe069af6a1764e07be909d7cf64add99
           Boot ID: b81bb73dc549484c8927e830e149eb55
    Virtualization: kvm
  Operating System: CentOS Linux 7 (Core)
       CPE OS Name: cpe:/o:centos:centos:7
            Kernel: Linux 3.10.0-862.6.3.el7.x86_64
      Architecture: x86-64

For more answers try to query all release files within the /etc directory:

$ cat /etc/*elease
CentOS Linux release 7.5.1804 (Core) 
NAME="CentOS Linux"
VERSION="7 (Core)"
ID="centos"
ID_LIKE="rhel fedora"
VERSION_ID="7"
PRETTY_NAME="CentOS Linux 7 (Core)"
ANSI_COLOR="0;31"
CPE_NAME="cpe:/o:centos:centos:7"
HOME_URL="https://www.centos.org/"
BUG_REPORT_URL="https://bugs.centos.org/"

CENTOS_MANTISBT_PROJECT="CentOS-7"
CENTOS_MANTISBT_PROJECT_VERSION="7"
REDHAT_SUPPORT_PRODUCT="centos"
REDHAT_SUPPORT_PRODUCT_VERSION="7"

CentOS Linux release 7.5.1804 (Core) 
CentOS Linux release 7.5.1804 (Core)

Bash script to check CentOS version

The following bash script can be used to obtain the CentOS version number given that the /etc/centos-release file exists and is populated.

The below script serves as an example, feel free to modify wherever appropriate.

#!/bin/bash

full=`cat /etc/centos-release | tr -dc '0-9.'`
major=$(cat /etc/centos-release | tr -dc '0-9.'|cut -d \. -f1)
minor=$(cat /etc/centos-release | tr -dc '0-9.'|cut -d \. -f2)
asynchronous=$(cat /etc/centos-release | tr -dc '0-9.'|cut -d \. -f3)

echo CentOS Version: $full
echo Major Relase: $major
echo Minor Relase: $minor
echo Asynchronous Relase: $asynchronous

Output:

$ ./check-centos-version.sh 
CentOS Version: 7.5.1804
Major Relase: 7
Minor Relase: 5
Asynchronous Relase: 1804

Python program to check CentOS version

The following python script will output the distribution name along with the OS version number:

#!/usr/bin/python

import platform
print platform.linux_distribution()

Alternatively, one can execute python code directly from the shell:

$ python -c 'import platform; print platform.linux_distribution()'

Output:

$ python check-centos-version.py 
('CentOS Linux', '7.5.1804', 'Core')

Mirror from

LinuxConfig - How to check CentOS version - http://linuxconfig.org/how-to-check-centos-version